Variation in healthcare use and health outcomes is a major concern for health policy. The availability of multi-dimensional administrative panel data sets has facilitated the study of the sources of variations. This chapter reviews the health economics literature using multi-dimensional panel data, focusing primarily on applications that decompose the variation in healthcare use into demand-side and supply-side (place- or provider-related) factors. Following the literature review, these methods are illustrated through the analysis of place- and patient-specific determinants of antibiotic consumption in Hungary. Finally, multi-dimensional panel data is applied to study the association between primary care availability and the use of antibiotics.